Hello, guitar and theory enthusiasts! 
Have burning questions about music theory? Join another of our Q&A sessions with Richard Coles, one of our Approved Teachers, to unlock the secrets of music theory!
NOTE:
The discussion topics are public, but access to the live sessions and archive recordings is restricted to PMT subscribers.
There are always a few parts that I can’t get yet, but some new puzzle pieces add to what I already got. I don’t learn with tons of effort, but slowly and I know I’m getting further.
Thanks a lot, Richard!
You’re doing a great job!
Dominique
@Richard_close2u Thank you for a great class!
That was actually my power chord question- I did put a message in the chat, but it wasn’t until you had already started answering the question, so it was a bit too late to be seen. Sorry about that!
Your answer ended up being really helpful for me- so thank you! I was mostly asking because I’m writing a lot of power chord based music and sometimes it’s hard for me to analyze what I’ve written 
I am very much in Justin’s camp of “if it sounds good, it is good” when I’m in the initial phases of writing a song. I do it using my ear/what sounds good and not thinking so much about structure or the key. I’m trying to get better at being able to analyze what I’ve written!
Richard will give you a better and more complete answer, but often, having the chords you can already narrow down what key it could be in and then, me personnally, I play the full chords and often can hear what the power chords are meant to be. At least, that works in many songs.